In many air handling systems and in particular, air conditioning systems, the conservation of both space and energy is of primary concern. Most room air conditioning units in use today are mounted in compact cabinets with the conditioned air being discharged from the unit through an elongated opening that extends horizontally across the face of the unit cabinet.
Typically, a series of parallelly aligned horizontal louvers are mounted in the discharge opening of the cabinet and a series of vertically aligned louvers are mounted behind the horizontal louvers. The horizontal louvers are connected to a programmed stepper motor by a rocker arm arrangement. The motor is programmed through the system controller to move the horizontal louvers a given number of steps in one direction and then a given number of steps in the opposite direction to establish a vertically expanded discharge air pattern which considerably enhances the units area of coverage. The vertical louvers in this arrangement can only be adjusted manually to change the direction of flow but not to expand the flow pattern.
To further expand the flow pattern in this type of system, a second stepper motor may be included which acts again through a linkage arrangement to step the louver a given number of steps in one direction and a given number of steps in the opposite direction to establish a further horizontally expanding the discharge flow pattern. The use of a second stepper motor typically required a second transformer to power the addition stepper motor or alternatively, a larger power supply. This approach resulted in the need for considerably more space in the power supply section of the unit and an increase in the unit cost as well as an increase in the amount of energy consumed by the unit.